This project focuses on developing new statistical methods, and applying new and existing statistical techniques, to analyze order-restricted toxicology data. One area of research focused on tests for dose-related trends in tumor rates. A general procedure was developed which can be applied to a wide array of problems, including some of those encountered in National Toxicology Program (NTP) studies. This new test is more powerful than the current (Poly-3) test and is robust with respect to the shape of the dose-response curve, the effects of dose on mortality, the spacings between doses, and the size of the background tumor rate. Similar techniques were developed to more efficiently estimate confidence intervals and to detect trends when the data are correlated. Also, new methods were developed to analyze data from heterogeneous sources (e.g. different laboratories).